Load platform supported on air cushion



Oct. 4, 1966 J. BORNEMAN 3,276,530

LOAD PLATFORM SUPPORTED ON AIR CUSHION Filed April 23, 1965 2Sheets-Sheet l INVENTORA.

Oct. 4, 1966 H. J. BORNEMAN LOAD PLATFORM SUPPORTED ON AIR CUSHION FiledApril 23, 1965 2 Sheets-Sheet 2 i7 mam/044.

United States Patent 3,276,530 I LOAD PLATFORM SUPPORTED ON AIR CUSHIONHarold J. Borneman, Detroit, Mich., assignor to Fruehauf Corporation,Detroit, Mich, a corporation of Michigan Filed Apr. 23, 1965, Ser. No.450,418 1 Claim. (Cl. 180-7) This invention relates generally tomaterial handling apparatus and more particularly to an improved ductingsystem for multiple ground-effect air pads of a materials handlingpallet.

Rapid advances in the state of the art of ground-effect machines and thegeneral acceptance thereof as a practical means for handling materialshave concentrated efforts to improve the efiiciency of such machines.The present invention is directed to a novel ducting system thatmaximizes the efiiciency of distribution of relatively low pressure airto a plurality of ground-effect air pads.

Accordingly, one object of the instant invention is an improved ductingsystem for multiple ground-effect air pads.

Another object is an integral ducting system for a materials handlingpallet which balances and controls air pressures within a plurality ofground-effect air pads.

Other objects and advantages of the present invention will be apparentfrom the following specification, claim and drawings wherein:

FIGURE 1 is a bottom plan view of a material handling pallet having aplurality of ground-effect air pads secured thereto;

FIG. 2 is a cross sectional view taken substantially along the line 22of FIGURE 1;

FIG. 3 is a cross sectional view taken substantially along the line 3-3of FIGURE 2;

FIG. 4 is a view looking in the direction toward the lower end of FIGURE1;

FIG. 5 is a cross sectional view taken substantially along the line 5-5of FIGURE 4, and

FIG. 6 is a view taken generally along the line 66 of FIGURE 5.

As seen in FIGURE 1 of the drawings, a material handling pallet 10 isprovided with a plurality of conventional air pads 12, 14, 16 and 18.The pads 12, 14, 16 and 18, which are commercially available from, forexample, General Motors Corporation, require an input of air atapproximately 2 to 4 pounds per square inch, the air flowing into anannular reservoir internally of the pads, respectively, thence outwardlythrough a plurality of apertures in the flexible diaphragms of the pads.

In accordance with the instant invention, the pallet 10 has acombination central structural member and duct 30 that extendslongitudinally of the pallet 10 and functions not only as the backboneof the pallet 10 but also as a duct or chamber to conduct relatively lowpressure air the full length of the pallet 10. The duct 30 is providedwith four laterally extending apertures, two of which are shown anddesignated by the numerals 32 and 34, which in turn communicate withlaterally extending ducts 36 and 38, respectively. The ducts 36 and 38are defined by extruded floor panels 39 having, as best seen in FIGURE3, a top panel 40, vertical ribs 42 and 44, and a bottom panel 46 whichdefines the duct 38. For the purpose of clarity, only the duct 38 willbe described in detail, it being understood that the description of theduct 38 is exemplary of the construction of each of the ducts leading tothe air bags 12, 14, 16 and 18.

The floor panels 39 are surrounded by an edge extrusion 50 which aids inretaining the panels 39 in a rigid assembly. The edge extrusions 50 havea skidplate 52 thereunder to support the pallet 10 when the air bags 12,14, 16 and 18 are deflated. Similarly, a skidplate 54 underlies thecenter member 30.

In accordance with another feature of the instant invention, the duct38, as well as the ducts leading to the air bags 12, 14 and 16, isprovided with an orifice plate 60 having an aperture 62 therein which isselected in accordance with loading of the pallet 10. The orifice plate60 is retained on one side by a cover plate 64 and on the other side bythe top panel 66 of the air pad 18. Orifice plates having apertures ofdifferent size can be substituted for the orifice plate 60 by removingthe air pad 18 from the bottom of the pallet 10 whereupon the orificeplate 60 drops out.

In accordance with yet another feature of the instant invention,opposite ends 70 and 72 of the duct 30, are provided with air inletvalves 74 and 76, respectively. As best seen in FIG. 6 of the drawings,the air inlet valve 74, which is exemplary of both valves 74 and 76,comprises a fiat resilient valve seat member 78 having an aperture 80therein for the acceptance of a complementary nozzle 82 on a line from asource of low pressure air (not shown). A fiat resilient valve member 84is disposed behind the member 78 so as to flex inwardly of the channel30 upon insertion of the nozzle 82. It will be appreciated that the airpressure differential on opposite sides of the valve member 84, willoperate to maintain the valve member 84 at the opposite end of thechannel 30 sealably biased against its valve seat 78. In this manner,eificiency of the air duct system is maximized.

What is claimed is:

Materials handling pallet comprising a substantially fiat loadsupporting surface,

a plurality of air pads underlying said surface,

a structural member defining a portion of the load supporting surface,said member extending centrally of said pallet defining a primary ductbetween said air pads,

a plurality of floor members extending laterally of said primary ductdefining secondary ducts com- Lnunicating with said primary duct andwith said air and an inlet flapper valve at both ends of said primaryduct for the acceptance of a low pressure air nozzle, each said valvecomprising a fiat valve seat having inlet aperture therein and a flatresilient member normally closing said aperture on the inside of saidseat, said resilient member being movable inwardly of said primary ductupon insertion of said nozzle, the resiliency of said resilient memberpermitting said member to flex into engagement with said valve seat toseal the aperture therein upon a relatively small increase in airpressure in said primary duct over ambient air pressure.

References Cited by the Examiner UNITED STATES PATENTS 2,918,183 12/1959Petersen et a1.

3,052,483 9/1962 Petersen 7 3,096,728 7/1963 Amann et a1. 180-73,121,401 2/1964 Fields 180-? 3,124,209 3/1964 Flipse 180-7 3,209,92910/1965 Petersen et a1. 180-7 FOREIGN PATENTS 924,834 5/ 1963 GreatBritain. 1,348,086 11/1963 France.

A. HARRY LEVY, Primary Examiner.

